This percussion apparatus includes a striking piston, a control distributor arranged to control a reciprocating movement of the striking piston, and a control device arranged to vary the striking stroke of the striking piston. The control device comprises a plurality of control channels, a control channel connected to the control distributor, a control slide movably mounted between a plurality of control positions, and an adjusting slide mounted in a receiving housing delimited by the control slide, the control slide and the adjusting slide delimiting a first adjusting chamber connected to the control channel and a second adjusting chamber connected to a the high-pressure fluid supply circuit. The control slide is movably mounted between a first position in which the first control chamber and the second adjusting chamber are connected and a second position in which the first control chamber and the second adjusting chamber are isolated.

This percussion apparatus includes a striking piston, a control distributor arranged to control a reciprocating movement of the striking piston, and a control device arranged to vary the striking stroke of the striking piston. The control device comprises a plurality of control channels, a control channel connected to the control distributor, a control slide movably mounted between a plurality of control positions, and an adjusting slide mounted in a receiving housing delimited by the control slide, the control slide and the adjusting slide delimiting a first adjusting chamber connected to the control channel and a second adjusting chamber connected to a the high-pressure fluid supply circuit. The control slide is movably mounted between a first position in which the first control chamber and the second adjusting chamber are connected and a second position in which the first control chamber and the second adjusting chamber are isolated.

A hammer drive mechanism for a hammer strike mechanism of a hammer drill is provided including: a drive shaft capable of being rotationally driven by a motor, a rod capable of reciprocatingly driving a piston, and a conversion mechanism that converts the rotary movement of the drive shaft into a reciprocating movement of the rod. The drive shaft comprises a first part connected to the conversion mechanism and a second part capable of being rotationally driven by a motor. The second part connects to the first part via at least one dampener such that rotary movement of the second part is transferred to the first part via the at least one dampener.

A hammer drive mechanism for a hammer strike mechanism of a hammer drill is provided including: a drive shaft capable of being rotationally driven by a motor, a rod capable of reciprocatingly driving a piston, and a conversion mechanism that converts the rotary movement of the drive shaft into a reciprocating movement of the rod. The drive shaft comprises a first part connected to the conversion mechanism and a second part capable of being rotationally driven by a motor. The second part connects to the first part via at least one dampener such that rotary movement of the second part is transferred to the first part via the at least one dampener.

A hydraulic hammering device that uses a scheme in which a front chamber is switched into communication with a low-pressure circuit when a piston advances, wherein occurrences of galling to the piston at a sliding contact portion with a front-chamber liner is reduced. The front chamber has the front-chamber liner fitted to an inner surface of a cylinder. A hydraulic chamber space communicating with the front chamber and filled with hydraulic oil is formed as a cushion chamber on the inner peripheral surface of a rear portion of the front-chamber liner. The cushion chamber has a second drain circuit (from first end face grooves to slits to second end face grooves), which is provided separately from a drain circuit that guides the hydraulic fluid passing through a liner bearing of the front-chamber liner to the low-pressure circuit.

A processor-controlled, energy-based therapy apparatus includes a pressure wave therapy device configured to provide therapeutic acoustic pulses to a patient and a processor that controls the output of the device. The pressure wave therapy device may include a control unit configured to control the pressure wave therapy device to deliver a treatment program, the treatment program comprising a plurality of acoustic pulses, each acoustic pulse comprising a pressure, the control unit including a memory storing patient-specific treatment information relating to a pain threshold of the patient; and a pain threshold indicator coupled to the control unit, the pain threshold indicator operable by the patient to provide an indication to the control unit of when a patient's pain threshold has been reached because an energy level delivered to the patient is unbearable.

A processor-controlled, energy-based therapy apparatus includes a pressure wave therapy device configured to provide therapeutic acoustic pulses to a patient and a processor that controls the output of the device. The pressure wave therapy device may include a control unit configured to control the pressure wave therapy device to deliver a treatment program, the treatment program comprising a plurality of acoustic pulses, each acoustic pulse comprising a pressure, the control unit including a memory storing patient-specific treatment information relating to a pain threshold of the patient; and a pain threshold indicator coupled to the control unit, the pain threshold indicator operable by the patient to provide an indication to the control unit of when a patient's pain threshold has been reached because an energy level delivered to the patient is unbearable.

This percussion apparatus includes a striking piston mounted so as to be displaced inside a piston cylinder and arranged to strike a tool; and a guide bearing comprising a guide surface configured to guide the striking piston during the displacements of the striking piston in the piston cylinder. The guide bearing includes a centering device configured to center the striking piston in the piston cylinder, the centering device comprising centering chambers formed in the guide surface and distributed around the striking piston, each centering chamber being fluidly connected to a high pressure fluid supply circuit; and at least one discharge groove formed in the guide surface of the guide bearing and located proximate to at least one of the centering chambers, the at least one discharge groove being fluidly connected to a low pressure circuit.

A hydraulic hammer is provided. The hydraulic hammer includes a fluid inlet configured to receive a pressurized fluid for running the hydraulic hammer and a fluid outlet for discharging hydraulic fluid from the hydraulic hammer. A bypass passage fluidly connects the fluid inlet and the fluid outlet, the bypass passage has a bypass inlet fluidly connected to the fluid inlet and a bypass outlet fluidly connected to the fluid outlet. An automatic shut-off valve is disposed in the bypass passage between the bypass inlet and the bypass outlet and is configured to open or close the bypass passage. The automatic shut-off valve is configured to open the bypass passage under pressure of the pressurized fluid on continuous running of the hydraulic hammer for a set time to stop the hammer.

A hydraulic hammer is provided. The hydraulic hammer includes a fluid inlet configured to receive a pressurized fluid for running the hydraulic hammer and a fluid outlet for discharging hydraulic fluid from the hydraulic hammer. A bypass passage fluidly connects the fluid inlet and the fluid outlet, the bypass passage has a bypass inlet fluidly connected to the fluid inlet and a bypass outlet fluidly connected to the fluid outlet. An automatic shut-off valve is disposed in the bypass passage between the bypass inlet and the bypass outlet and is configured to open or close the bypass passage. The automatic shut-off valve is configured to open the bypass passage under pressure of the pressurized fluid on continuous running of the hydraulic hammer for a set time to stop the hammer.